80685540 has 216 divisors, whose sum is σ = 279632808. Its totient is φ = 18708480.

The previous prime is 80685463. The next prime is 80685547. The reversal of 80685540 is 4558608.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 50808384 + 29877156 = 7128^2 + 5466^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 80685495 and 80685504.

It is not an unprimeable number, because it can be changed into a prime (80685547) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1967920 + ... + 1967960.

Almost surely, 2^80685540 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 80685540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139816404).

80685540 is an abundant number, since it is smaller than the sum of its proper divisors (198947268).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

80685540 is a wasteful number, since it uses less digits than its factorization.

80685540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127 (or 93 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 36.

The square root of 80685540 is about 8982.5130114017. The cubic root of 80685540 is about 432.1142316229.

It can be divided in two parts, 80685 and 540, that added together give a square (81225 = 285²).

The spelling of 80685540 in words is "eighty million, six hundred eighty-five thousand, five hundred forty".